Intermedin Protects HUVECs From Hypoxia/reoxygenation Injury Via Wnt/?-catenin Signaling Pathway

Purpose:Intermedin?IMD?is a member of the calcitonin gene-related peptide?CGRP?super family and a pro-angiogenic factor.In the present study,we identified activation of the Wnt/?-catenin signaling pathway by IMD.Method:Adding CoCl₂ HUVECs was used to establish an in vitro model.The migration of HUVECs was measured by wound healing assays and transwell migration assays.Capillary formation was measured using tube formation assays.Immunocytochemistry?ICC?analysis was used to evaluate VEGF and RAMP2 expression in HUVECs.The relevant signaling molecules were detected with western blot.Result:Our study show that IMD could promote H/R impaired HUVECs migration and tube formation in vitro?p<0.05?.On the other hand,inhibition of Wnt/?-catenin signaling led to suppression of this promotion of migration and tube formation?p<0.05?.This result suggests that Wnt/?-catenin signaling is correlated to IMD induced angiogenesis.Analysis of results from ICC assays indicated that IMD works through increasing levels of VEGF and RAMP2?p<0.05?.Meanwhile,the Wnt/?-catenin signaling specific inhibitor IWR-1-endo was shown to down-regulate VEGF and RAMP2 expression?p<0.05?.Western blot results further confirmed the signaling mechanism by which IMD promotes angiogenesis?p<0.05?.Conclusion:Our study revealed that exogenous IMD could induced Wnt/?-catenin signaling to help neovascularization in vitro.The activation of Wnt/?-catenin signaling specifically up-regulates the expression of VEGF and RAMP2.